Gas ProductionCharacteristicsAnd In Vitro Digestibility OfSlow-ReleaseUrea Based On Gewang (<i>Corypha Utan</i> Lamk.) And Tapioca Stem Meal

Abstract This study evaluated the gas production characteristics and digestibility value of slow-release urea (SRU) products based on gewang (putak) and tapioca starch in vitro. SRU products were made by cooking a mixture of gewang stem fillings and/or tapioca with urea in an autoclave at 135°C, 186 pKa pressure for 60 minutes. The treatments applied were 0%, 4%, and 6% urea levels in each carbohydrate source, namely putak flour (TP0, TP4, TP6), putak starch (PP0, PP4, PP6), and tapioca (TT0, TT4, TT6). The study was conducted using the in vitro gas production method and was designed using a group randomized design with 3 treatments and 3 replicates. The fermentation kinetics of total gas production followed an exponential model Y = b*(1 - e −ct ). Data were analyzed using analysis of variance (ANOVA) and Duncan’s multiple range test. The results showed potential gas production and digestibility increased with increased urea levels in SRU products. Gas production for 48 hours ranged from 194.05 (mL/500 mg DM) to 326.83 (mL/500 mg DM), DM digestibility from 80.4% to 87.9%, and OM digestibility from 87.7% to 94.9%. It was concluded that gas production, dry matter, and organic matter digestibility in vitro of slow-release urea products with a 6% urea level based on putak flour did not differ from those based on putak starch and tapioca. Slow-release urea products using 6% urea in putak starch can be used as a cattle ration supplement. This research highlights the importance of sustainable practices in the livestock industry through optimizing the use of SRUs to improve ruminant production, economic viability, and environmental management.